From ee9bb4de9519481eb245ec23317b06a10eff493f Mon Sep 17 00:00:00 2001
From: Jeff Dike <jdike@addtoit.com>
Date: Mon, 4 Feb 2008 22:31:10 -0800
Subject: [PATCH] --- yaml --- r: 83207 b: refs/heads/master c:
 00a905e6145ba200308a6a13e00248b85c600bd0 h: refs/heads/master i:   83205:
 7ab65008247e683d847a5def4037b894c71ff3c7   83203:
 5f7e98026077230600bfd81540cbcd6e9b8255dd   83199:
 c9fbca14f9a8d49316d64b6916c94aaf8f730ebc v: v3

---
 [refs]                          |  2 +-
 trunk/arch/um/kernel/skas/mmu.c | 14 +++++++++++++-
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/[refs] b/[refs]
index e9f62915b5a0..3b0bb544716b 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 1aa351a308d2c3ddb92b6cc45083fc54271d0010
+refs/heads/master: 00a905e6145ba200308a6a13e00248b85c600bd0
diff --git a/trunk/arch/um/kernel/skas/mmu.c b/trunk/arch/um/kernel/skas/mmu.c
index e8dc8540d444..78b3e9f69d57 100644
--- a/trunk/arch/um/kernel/skas/mmu.c
+++ b/trunk/arch/um/kernel/skas/mmu.c
@@ -164,8 +164,20 @@ void destroy_context(struct mm_struct *mm)
 
 	if (proc_mm)
 		os_close_file(mmu->id.u.mm_fd);
-	else
+	else {
+		/*
+		 * If init_new_context wasn't called, this will be
+		 * zero, resulting in a kill(0), which will result in the
+		 * whole UML suddenly dying.  Also, cover negative and
+		 * 1 cases, since they shouldn't happen either.
+		 */
+		if (mmu->id.u.pid < 2) {
+			printk(KERN_ERR "corrupt mm_context - pid = %d\n",
+			       mmu->id.u.pid);
+			return;
+		}
 		os_kill_ptraced_process(mmu->id.u.pid, 1);
+	}
 
 	if (skas_needs_stub)
 		free_page(mmu->id.stack);